Well, If you're gigging alot, you probably wouldn't want to be dragging
around another keyboard, so I would recommend getting a rack sampler of some
kind.
Almost any will do: emu Emax II's & Ultra series are pretty cheap these
days, also very intuitive and easy to use.
the Akai s6000/5000 models are also getting down there in price and also
have USB options as well as a detachable lcd interface that makes
programming less likely to turn you into a hunchback.
The Yamaha ex5 comes to mind but it's pretty hard to find, plus even if you
can find one with the scsi option, the scsi speed is notoriousy slow.
On the other hand, if you want something more versatile, built like a tank
and still supported by the maker, I'd highly recommend a Kurzweil K2000 (or
any 'k' series, the K2500 is getting pretty cheap,too), they can come with
the sampling option, sound roms etc. and the keyboard version is worth it
just as a midi controller.
All the above mentioned should be in the comfortable $500usd or less range.
Now that I think of it an Emu ESI (insert number here) should go for $200
or less (probably less these days).
Lastly, yes that SU10 looks like a handy little unit, highly portable and
runs on batteries, probably the perfect thing for just triggering animal
noises from a keyboard, in fact there's one on
Ebay<
http://cgi.ebay.ca/Yamaha-SU10-Sampler-with-Live-Ribbon-Controller_W0QQitemZ200146837061QQihZ010QQcategoryZ38070QQssPageNameZWDVWQQrdZ1QQcmdZViewItem>right
now.
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